The presently disclosed subject matter relates to an apparatus for monitoring biological information of a patient or the like.
Among apparatuses for measuring biological information having a periodically changing value such as the arterial oxygen saturation (SpO2) or the end-tidal carbon dioxide concentration (ETCO2), known is an apparatus which outputs a sound in synchronization with the period of the biological information (for example, see Japanese Patent No. 3273295).
In the apparatus disclosed in Japanese Patent No. 3273295, in order to enable the user to identify the measurement value without requiring visual reading of the value, the tone scale of the output sound is changed in accordance with the value of biological information of the measurement target. However, it is difficult for a user having no sense of absolute pitch to discriminate small differences between scales to identify the measurement value.